polyvinyl acetal sponge is extremely hydrophilic (absorbent) because of OH-radicals in the molecular structure and the capillary action caused by it’s uniform pore structure.The result is outstanding absorption power.polyvinyl acetal sponge products can rapidly soak up fluids, thereby drying surfaces much faster than other materials.This material is completely open cell and each of it’s pores is not independent, but interconnected, unlike urethane or rubber products made by gas pore forming